1. Field of Invention
The invention provides a clamping device, and a backlight module and a display apparatus utilizing the clamping device. More particularly, the invention provides a clamping device that makes assembly easier, and a backlight module and a display apparatus utilizing the clamping device.
2. Description of Related Art
Because the display medium, i.e. the liquid crystals, in liquid crystal display (LCD) panels do not illuminate, each LCD apparatus must include an additional light source. LCD apparatuses can be sorted by the types of the utilized light sources. Reflective LCD apparatuses, transmissive LCD apparatuses, and trans-flective LCD apparatuses are three popular types of LCD apparatuses. In either a transmissive LCD apparatus or a trans-flective LCD apparatus, a backlight module is used to provide the surface light source required by the LCD panel.
FIG. 1A is a top view diagram of a conventional LCD apparatus using a side-type backlight module. FIG. 1B is a schematic diagram showing the enlarged area A of FIG. 1A. FIG. 1C is a 3-dimensional diagram showing the cross-section along the A-A′ direction of FIG. 1A. FIG. 1D is a top view diagram of the metal frame of the backlight module and the resin frame of the LCD apparatus of FIG. 1A. Refer to FIGS. 1A˜1C first. The LCD apparatus 100 includes an LCD panel 110, a metal frame 120, a resin frame 130, a light source module 150, and a circuit board 140, wherein the light source module 150 is only shown in FIG. 1C. The circuit board 140 is electrically connected to the LCD panel 110 and is located on a side of the LCD panel 110. The circuit board 140 and the LCD panel 110 are interconnected but do not overlap. In other words, rather than being bent to the back of the LCD panel 110, the circuit board 140 is arranged side-by-side with the LCD panel 110. Furthermore, the metal frame 120 and the resin frame 130 clamps the light source module 150 and the LCD panel 110.
Refer to FIGS. 1C˜1D. The light source module 150 includes a light source 152, a light guide plate 160, and an optical film 170. The light source module 150 and the metal frame 120 form a backlight module. The light source 152 is located on a side of the light guide plate 160. The optical film 170 lies between the light guide plate 160 and the LCD panel 110. The resin frame 130 and the metal frame 120 provide a chamber structure for the LCD panel 110 and the light source module 150 to be put therein.
Specifically, a side of the metal frame 120 is bent to form a bearing structure 124. The bearing structure 124 accommodates the light source 152, serves as a reflective cover, and clamps the light guide plate 160. The bearing structure 124 can reflect light to the light guide plate 160 to enhance the efficiency of light utility and decrease light leakage.
Herein, the light source 152 of the LCD apparatus 100 is structured as a light emitting diode (LED) light bar. To assemble the light source 152, a side of a reflective tape is adhered to the LED light bar first. Then, another side of the reflective tape is adhered to the bearing structure 124 of the metal frame 120.
However, it can be seen from FIG. 1C that the bearing structure 124 approximately has a U-shape. In addition, the light source 152 is relatively thin; the corresponding U-shape opening of the bearing structure 124 is relatively small. These characteristics make it difficult to fasten the light source 152 and to confirm that all the parts are properly positioned when assembling the light source 152. Particularly, it's difficult to adjust the position of the light guide plate 160 during the assembly process. As a result, the manufacturing efficiency and yield rate are relatively low.
Accordingly, to alleviate the difficulty in the assembly process and resolve the positioning hardship, the industry of backlight module needs a proper design for the metal frame and the reflective structure of the light source.